how to set multiple CSS style properties in typescript for an element?

93,948

Solution 1

Try using setAttribute. TypeScript does not have the style property on Element.

element.setAttribute("style", "color:red; border: 1px solid blue;");

Some related discussion in this GitHub issue: https://github.com/Microsoft/TypeScript/issues/3263

Solution 2

Just a little late to the party, but anyway...

The actual problem is not that style is not defined on Element. The word Element at the beginning of Element implicitly has an 'any' type because index expression is not of type 'number'. (property) HTMLElement.style: CSSStyleDeclaration is just the first word in a sentence and therefore uppercased. Means it does not relate in any way to the Element object - which is quite confusing.

However, the error message means that you are trying to access a property using the subscript operator [] with an incorrectly typed index. In your case your key is of type string but HTMLElement.style is a CSSStyleDeclaration object which has an index signature of [index: number]: string and consequently requires your key to be of type number.

The index signature comes from the typescript/lib/lib.dom.d.ts declaration file in your TypeScript installation. There you will find CSSStyleDeclaration.

So what you can do is simply cast to any like so:

(<any>element.style)[key] = attr[key];

It's not the best solution but it works and is straightforward. It also does not require you to stringify your styles like it would be necessary when you use element.setAttribute.

Solution 3

I hope this helps you or someone else...

You can achieve this using a HTLMDivElement and the CSSStyleDeclaration contained within it. eg.

var container: HTMLDivElement;

container.style.color = "red";
container.style.fontSize = "12px";
container.style.marginTop = "5px";

This also applies to other classes that inherit from HTMLElement and have a style property (for example HTMLBodyElement.

Solution 4

The API you were searching for is: https://developer.mozilla.org/en-US/docs/Web/API/CSSStyleDeclaration/setProperty

public static setStyleAttribute(element: HTMLElement, attrs: { [key: string]: Object }): void {
    if (attrs !== undefined) {
        Object.keys(attrs).forEach((key: string) => {
            element.style.setProperty(key, attrs[key]);
        });
    }
}

And hyphen is not allowed in object keys, so use ' here, too:

let elem: HTMLElement = document.getElementById('myDiv');
setStyleAttribute(elem, {'font-size':'12px', color: 'red', 'margin-top': '5px'});

Solution 5

you can use this for a single element, and iterate over it to make it dynamic

let el: HTMLElement = document.getElementById('elementID');

el.style.height = "500px";
Share:
93,948

Related videos on Youtube

Srinivasan Natarajan
Author by

Srinivasan Natarajan

Updated on April 08, 2022

Comments

  • Srinivasan Natarajan
    Srinivasan Natarajan over 1 year

    Please consider the below snippet. i need to set multiple CSS properties in typescript. for that i have tried the below code.

    public static setStyleAttribute(element: HTMLElement, attrs: { [key: string]: Object }): void {
            if (attrs !== undefined) {
                Object.keys(attrs).forEach((key: string) => {
                    element.style[key] = attrs[key];
                });
            }
        }
    

    for the above code i need to pass the parameters as

    let elem: HTMLElement = document.getElementById('myDiv');
    setStyleAttribute(elem, {font-size:'12px', color : 'red' , margin-top: '5px'});
    

    But the above code throws error(tslint) as Element implicitly has an 'any' type because index expression is not of type 'number'. (property) HTMLElement.style: CSSStyleDeclaration.

    Please help me !!!

    • Srinivasan Natarajan
      Srinivasan Natarajan over 7 years
      error thrown in this line .......... element.style[key]
  • Srinivasan Natarajan
    Srinivasan Natarajan over 7 years
    may be for some one. not for my scenario..:)
  • eddipedia
    eddipedia over 5 years
    BTW: Does anyone know why the CSSStyleDeclaration in TypeScript's declarations file has that number-based index signature instead of a string-based? Makes no sense to me.
  • HolgerJeromin
    HolgerJeromin about 5 years
    It reflects the browser. Try: myElement.style[0] to access the first style of myElement.
  • HolgerJeromin
    HolgerJeromin about 5 years
    This code has the side effect, that it kills all old style definitions.
  • theUtherSide
    theUtherSide about 5 years
    That's true! You'd need to use element.getAttribute('style') and merge the two together to maintain existing styles.
  • evnp
    evnp over 2 years
    This should be the accepted answer. TypeScript's CSSStyleDeclaration has number-based indexing (referenced in comments on other answers here) so string keys don't work. setProperty accepts string keys and has the same effect as style[key] = val without resorting to unsafe typing. Thanks @HolgerJeromin
  • user697576
    user697576 over 2 years
    Here's the related issue on github github.com/microsoft/TypeScript/issues/17827
  • Geryson
    Geryson almost 2 years
    I've used this with TypeScript / Angular. Normally, document.getElementById() can return as an Element type, make sure you use let el: HTMLElement = <HTMLElement>document.getElementById('elementID'); to change it. Thanks!